Dissertations / Theses: 'Faults (geology)'

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Soden, Aisling Mary. "The initiation and evolution of ignimbrite faults, Gran Canaria, Spain." Connect to e-thesis, 2008. http://theses.gla.ac.uk/191/.

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Thesis (Ph.D.) - University of Glasgow, 2008.
Ph.D. thesis submitted to the Department of Geographical and Earth Sciences, Faculty of Physical Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.

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Kim, Young-Seog. "Damage structures and fault evolution around strike-slip faults." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340659.

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Hoeft, Jeffrey Simon. "Temporal variations in slip-rate along the Lone Mountain fault, Western Nevada." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33862.

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Late Pleistocene displacement along the Lone Mountain fault suggests the Silver Peak-Lone Mountain (SPLM) extensional complex is an important structure in accommodating and transferring strain within the eastern California shear zone (ECSZ) and Walker Lane. Using geologic and geomorphic mapping, differential global positioning system surveys, and terrestrial cosmogenic nuclide (TCN) geochronology, we determined rates of extension across the Lone Mountain fault in western Nevada. The Lone Mountain fault is the northeastern component of the SPLM extensional complex, and is characterized by a series of down-to-the-northwest normal faults that offset the northwestern Lone Mountain and Weepah Hills piedmonts. We mapped eight distinct alluvial fan deposits and dated three of the surfaces using ¹⁰BE TCN geochronology, yielding ages of 16.5 +/- 1.2 ka, 92.3 +/- 8.6 ka, and 142.2 +/- 19.5 ka for the Q3b, Q2c, and Q2b deposits, respectively. The ages were combined with scarp profile measurements across the displaced fans to obtain minimum rates of extension; the Q2b and Q2c surfaces yield an extension rate between 0.1 +/- 0.1 and 0.2 +/- 01 mm/yr and the Q3b surface yields a rate of 0.2 +/-.1 to 0.4 +/- 0.1 mm/yr, depending on the dip of the fault. Active extension on the Lone Mountain fault suggests that it helps partition strain off of the major strike-slip faults in the northern ECSZ and transfers deformation around the Mina Deflection northward into the Walker Lane. Combining our results with estimates from other faults accommodating dextral shear in the northern ECSZ reveals an apparent discrepancy between short- and long-term rates of strain accumulation and release. If strain rates have remained constant since the late Pleistocene, this could reflect transient strain accumulation, similar to the Mojave segment of the ECSZ. However, our data also suggest an increase in strain rates between ~92 ka and ~17 ka, and possibly to present day, which may also help explain the mismatch between long- and short-term rates of deformation in the region.

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Sturms, Jason M. "Surficial mapping and kinematic modeling of the St. Clair thrust fault, Monroe County, West Virginia." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5597.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains vii, 84 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 75-78).

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McClay, K. R. "Structural geology and tectonics /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09SD/09sdm126.pdf.

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Zhang, Hongwei Niemi Tina M. "Paleoseismic studies of the northern San Andreas Fault at Vedanta marsh site, Olema, California." Diss., UMK access, 2005.

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Thesis (Ph. D.)--Dept. of Geosciences and School of Computing and Engineering. University of Missouri--Kansas City, 2005.
"A dissertation in geosciences and computer networking." Advisor: Tina M. Niemi. Typescript. Vita. Description based on contents viewed Mar. 12, 2007; title from "catalog record" of the print edition. Includes bibliographical references (leaves 331-341). Online version of the print edition.

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Guiltinan, Tiffany. "Potentially active faults in central Mongolia." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1584413.

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The activity of the Ereen Uul fault and the Sanglin Dalai Nurr fault in central Mongolia has not been studied in detail. The Erren Uul fault is a normal fault located 45 km southeast from Harhorin and the Sanglin Dalai Nurr fault is a right-lateral strike-slip fault located 30 km south of Harhorin next to the Hangay Mountains. Remote sensing and field observations were used to refine a map by the Mongolian Geologic Survey at a scale of 1:1,000,000 to a scale of 1:100,000. This new map covers an area of 8,072 km². The basin asymmetry factor, stream length-gradient index, and hypsometric curves were developed for basins adjacent to these faults. These geomorphic indices along with the refined map were used to conclude that the Ereen Uul and Sanglin Dalai Nurr faults are active.

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Chanpura, Rajesh. "Fault reactivation as a result of reservoir depletion." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/21714.

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Williams, Charles Addison Jr. "Numerical modeling of fault formation and the dynamics of existing faults." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185125.

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This research is an investigation into two different aspects of the faulting process. The first part of the study focuses on the initial stages of fault formation, while the second analyzes the deformation produced by an existing fault. The section on fault formation is an attempt to determine whether slip on an existing fault has a significant effect on the formation of subsequent faults. A two-dimensional elastic finite element technique is used to examine the system of stresses produced by slip on an initial fault, assuming that deformation occurs either elastically or by brittle failure. A Mohr-Coulomb failure criterion is used to determine the most likely region of secondary fault initiation. A strain energy criterion is then used to find the preferred direction of fault propagation. The study on fault formation is subdivided into two sections representing two idealized tectonic environments: purely extensional and purely compressional. The section on extensional fault formation explains the prevalence of grabens in extensional tectonic regimes as a consequence of the stress perturbations due to slip on an initial normal fault. Slip on the initial fault produces a region of high proximity to failure at the surface of the downthrown block. A secondary fault would be expected to initiate in this region. The direction of propagation of this fault that most effectively relieves the shear stress (and therefore minimizes the total strain energy) is toward the initial fault, resulting in an antithetic orientation, or graben. The width of the graben is found to be controlled by the depth of the initial normal fault, rather than the depth to a change in material properties. The study of compressional fault formation indicates that, except for steeply-dipping faults, the presence of an initial thrust fault tends to suppress the formation of other faults in its vicinity. However, if a secondary fault initiates near an initial thrust fault, the direction in which it propagates will be influenced by the presence of the initial fault. The way in which it is influenced is dependent on the fault dip. The final part of this study examines the deformation produced by repeated earthquake cycles on the San Andreas fault in southern California. A three-dimensional, time-dependent kinematic finite element model is used to investigate the influence of slip distribution and rheological parameters on the predicted horizontal and vertical deformation. The models include depth-varying rheological properties and power-law viscoelastic behavior. The predicted deformation patterns are fairly sensitive to the parameters used in this study. Of particular importance is the calculation of vertical uplift rate since, in many cases, models that cannot be distinguished from each other on the basis of horizontal deformation may produce distinctive vertical uplift patterns.

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Skamvetsaki, Angela. "Deformation band development near meso-scale faults in porous sandstones : implications for fault seal prediction." Thesis, Royal Holloway, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289595.

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Seismic-scale faults are generally associated with clusters of subresolution faults, and the issue of how to predict the latter's numbers and distribution has been the subject of much recent debate due to its bearing on accurate fault seal evalution. One important class of subseismic-scale faults are deformation bands, which are tabular shear zones commonly formed in reservoir-quality aeolian and fluvial sandstone successions. Relevant outcrop and oil field case studies suggest such structures can reduce host rock permeability by up to four orders of magnitude, yet there is little published infonnation on the controls on their localisation and their relationship to larger-scale fault growth processes. This study addresses this knowledge gap and reports results of integrated structural, statistical, probe permeability and hydromechanical test investigations on fault-controlled deformation band arrays from two areas, Cullercoats Bay in NE England and the Clair Field, offshore NW UK continental shelf. Key aims are to examine the mesoand microscopic architecture of these band networks, establish their general evolution and elucidate their relationship to large fault development. Ancillary concerns include the expansion of the still limited database of deformation band spatial attributes, and assessment of the main areas of sensitivity in the analytical and statistical techniques used to describe these and other similar fault systems. Deformation bands at Cullercoats occur within the aeolian Yellow Sands of Permian age in the hanging wall of the Ninety Fathom fault, a major normal fault episodically active from the Carboniferous until at least Permian times. Structural analysis suggests that this band population was initiated as a result of dextral or oblique-dextral slip on the underlying Carboniferous Ninety Fathom fault, and was then progressively modified during the propagation of this fault into the overlying sediment cover and attendant development of fault-related folding and second-order faulting. In Clair, deformation bands are associated with arrays of calcite-filled veins and are inferred to have formed in response to fault-triggered fluid redistribution processes within the variably lithified aeolian-fluvial sandstones of the Clair Group. Statistical and mechanical evidence from both areas indicates that deformation band growth preceded major fault formation there, a finding that is consistent with the predictions of post-yield fracture mechanics models for process zone development at fault tips. A further common result from the two localities is that deformation band development and permeability character appears to be primarily controlled by the porosity and loading history of the faulted sandstones; therefore, assessment of the time of faulting should be a first step for determining whether a given subsurface fault is likely to be associated with deformation bands. Specific conclusions are: (1) The damage zones of band-related faults in porous sandstones scale linearly with fault displacement. (2) Deformation band densities decay quasi-exponentially with increasing distance from the faults within whose damage zones they occur. (3) Deformation band spacing distributions depart from strict self-similarity owing to the confinement of the bands within discrete mechanical horizons, yet their overall statistical character attests to multifractal scaling and Levytype stable behaviour. (4) Because of the observed deviations of deformation band statistics from simple power-law scaling laws, extrapolation of seismic-scale fault populations down to the deformation band level may give incorrect estimates of band numbers and/or size attributes. (5) Deformation bands display a broad range of microstructures and permeability signatures depending on host rock lithology, degree of compaction, previous stress history and local deformation details. (6) Despite their low-very low static permeabilities, deformation bands may act as fluid pathways during their development or reactivation in a subsequent tectonic event. (7) Application of standard statistical and probe permeability approaches to deformation band characterisation should be approached with caution due to problems inherent in the nature of deformation band systems itself. (8) Based on microstructural evidence and diagenetic and mechanical considerations deformation in the two study areas may have taken place at - 1.5-2 km, under maximum effective confining pressures of around 30 MPa.

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Bayliss, Brian G. Cronin Vincent S. "Test of a method for recognizing unmapped seismogenic faults." Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5035.

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Higgs, William G. "The geometries and kinematics of extensional faults." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261458.

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Canalda, Sabrina Michelle. "Magnitude of right-lateral offset on the southern Death Valley fault zone from miocene volcanic assemblages." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Tsang, Hin-sui Calvin. "The diagnostic features of fault zones from core samples and outcrop study in Hong Kong." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B42577676.

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Bie, Lidong. "Investigating the earthquake cycle of normal faults." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2036419/.

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Geodetic observations of crustal deformation through the earthquake cycle provide unique opportunities to gain essential knowledge of faulting mechanisms, lithospheric rheology, and fault interaction. Normal faults, an integral geologic unit responsible for crustal deformation, are specifically investigated in this thesis, via three case studies in two significantly different tectonic environments: the 2008 Mw 6.3 Damxung and Mw 7.1 Yutian earthquakes on the Tibetan Plateau, and the 2005 Mw 7.8 Tarapaca earthquake in the northern Chile subduction zone. To move toward realistic slip models, I consider crustal layering for the Damxung earthquake, and non-planar rupture for the Yutian earthquake. The Damxung study shows that assuming a homogeneous crust underestimates the depth of slip and overestimates the magnitude, in comparison to a crustal model with a weak sedimentary lid. A curved fault model composed of triangular dislocation elements (TDEs) for the Yutian earthquake recovers the geodetic observation better than rectangular fault segments. Normal faulting earthquakes are characterized by shallow slip deficit, which is partially compensated by patchy afterslip around, but no deeper than, the coseismic rupture. The complementary and partially-overlapping relationship between coseismic slip and afterslip implies complexity of frictional properties in both down-dip and along-strike directions. Postseismic deformation induced by viscoelastic relaxation (VER) following normal faulting earthquakes is fundamentally different in pattern from that produced by afterslip. This difference enables identification of afterslip as the major postseismic mechanism for the Damxung and Yutian earthquakes, and VER for the Tarapaca earthquake. In addition to understanding the faulting mechanism, I also place constraints on local rheological structure. In central Tibet, where the Damxung earthquake occurred, lack of noticeable VER-related signal allows a lower bound of 1 × 1018 Pa s for the viscosity of the lower crust/upper mantle. In northern Chile, geodetic observations following the Tarapaca earthquake indicate a weak layer with viscosity of 4 – 8 × 10^18 Pa s beneath a higher-viscosity lower crust and mantle lithosphere, and a strong continental forearc. Based on the co- and post-seismic models, I investigate fault interaction from a perspective of static stress change. Stress computation suggests that the 2014 Mw 6.9 strike-slip event close to the Altyn Tagh fault occurred on a fault that was positively stressed by the Yutian earthquake, and the Altyn Tagh fault to the east of the 2014 rupture is a potential locus for future failure. Although the Coulomb stress change on the 2014 Iquique earthquake rupture is negative due to the Tarapaca earthquake and its postseismic VER process, positive loading on the shallow-dipping nodal plane of its M 6.7 preshock suggests that the Tarapaca earthquake may have acted as an indirect trigger of the 2014 Iquique earthquake. Both studies reveal the role played by normal faults in interacting with other types of faults and have implications for seismic hazard assessment.

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Hayman, Nicholas W. "Structure and petrology of gouge and breccia bearing shallow crustal shear zones of detachment faults in Death Valley, California /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6699.

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Roberts, Gerald Patrick. "Deformation and diagenetic histories around foreland thrust faults." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6258/.

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This thesis is concerned with the relationship between deformation and fluid flow along thrust zones. The study was carried out in the Vercors, French Sub-Alpine Chains foreland thrust belt. Study of the thermal alteration of organic matter within the area suggests that prior to west-north-west directed thrusting within the Vercors basin in post middle Miocene times, the rocks now exposed at the surface had not been buried beneath a large thickness of foredeep sediments and remained within the diagenetic realm. Deeper buried levels within the stratigraphy passed into the hydrocarbon generation window prior to thrusting within the Vercors basin. The rocks presently exposed at the surface also remained in the diagenetic realm during and after the thrusting which suggests that thrust sheet loading did not significantly contribute to thermal alteration of organic matter. The structures of the thrust belt may have been possible structural traps for any hydrocarbons which underwent re-migration during the thrusting. The structures have been exhumed by erosion during isostatic uplift. The Rencurel Thrust and overlying Rencurel Thrust Sheet were selected for special study as they are of regional structural importance. The thrust emplaces Urgonian limestones onto Miocene molasse sediments at present erosion levels. The thrust sheet is internally deformed by thrusts and folds. Structural data indicate that the deformation within the thrust sheet and within the Rencurel Thrust Zone occurred during one kinematically linked phase of thrusting. The Rencurel Thrust Zone itself is around 100 metres thick. The higher part of the thrust zone is composed of an array of minor faults developed within the Urgonian. These fault zones are generally less than 10cm wide and are coated in fault gouge. This array of faults is underlain by a gouge zone along the thrust contact between the Urgonian and the Miocene which is several metres thick. The gouge zones were all formed during the action of diffusive mass transfer (DMT) and cataclasis as deformation mechanisms. The wall-rocks to the gouge zones are relatively undeformed by the action of cataclasis. Cataclasis is dilatant and produces fracture porosity which increases the permeability of the fault zones whilst DMT reduces the porosity and permeability of the fault zones due to cement precipitation and pressure dissolution. Cross- cutting relationships between the microstructures indicating the action of cataclasis and DMT, suggest that the porosity and permeability of the fault rocks changed in a complex manner during the incremental deformation. This has important implications for assessing syn-kinematic fluid migration through fault zones. The fault rocks exposed at the surface today are relatively impermeable compared to undeformed wall-rocks away from the fault zone which have permeabilities comparable to those found within hydrocarbon reservoirs. The thrust zone may have been a seal in the sub-surface after the cessation of thrusting but prior to uplift and erosion. Early distributed deformation produced an array of minor faults within the Urgonian. Cataclasis had ceased along these faults before later deformation became localised along the gouge zone which exists along the thrust contact between the Urgonian and the Miocene rocks. Early deformation was accompanied by the migration through fracture porosity of pore waters which were saturated with respect to calcite and had interacted with organic matter which was being thermally altered. This fluid flow system was not connected to fluid flow higher in the stratigraphy which resulted in the precipitation of ferroan calcite within fracture porosity in the Senonian limestones. Late deformation within the thrust zone was accompanied by the migration of hydrocarbons and pore waters saturated with respect to calcite and pyrite. All the pore waters involved in migration through the active thrust zone seem to have migrated up-dip. They migrated from levels in the stratigraphy where organic metamorphism and the maturation of hydrocarbons were occurring to levels in the deformed section which have always remained within the diagenetic realm. Ferroan calcite, pyrite and traces of hydrocarbons have not been found outside the gouge zone along the thrust contact between the Urgonian and Miocene. The fracturing which occurred to open this migration pathway did not re- fracture the inactive minor faults which were impermeable at this time. Fluid migration at this time was confined to beneath the zone of impermeable minor faults in the Urgonian and did not contribute to the diagenesis of the rocks above the thrust zone. Hydrocarbons could not have entered the hanging-wall anticline above the thrust zone from this migration pathway. The fracturing at this time did not produce connected fracture networks pervasively throughout the thrust zone which suggests that the deformation may not have released large amounts of energy in the form of seismic waves.

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Scharer, Katherine Maxine. "Earthquakes to mountains : fault behavior of the San Andreas Fault and active tectonics of the Chinese Tian Shan /." view abstract or download file of text, 2005. http://wwwlib.umi.com/cr/uoregon/fullcit?p3164085.

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Thesis (Ph. D.)--University of Oregon, 2005.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 173-185). Also available for download via the World Wide Web; free to University of Oregon users.

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Newman, Patrick James. "The Work Budget of Rough Faults." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1374070945.

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Redondo, Lopez Maria Teresa. "Hangingwall deformation and kinematics in listric extensional growth faults." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300496.

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Oliver, David Owen. "The development of structural patterns above reactivated basement faults." Thesis, Boston Spa, U.K. : British Library Document Supply Centre, 1987. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.263240.

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22

Kinabo, Baraka Damas. "Incipient continental rifting: insights from the Okavango Rift Zone, northwestern Botswana." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/kinabo_09007dcc.8048de9a.pdf.

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Thesis (Ph. D.)--University of Missouri--Rolla, 2007.
Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 4, 2008) Includes bibliographical references.

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Drakos, Peter S. "Tertiary stratigraphy and structure of the southern Lake Range northwest Nevada assessment of kinematic links between strike-slip and normal faults in the northern Walker Lane /." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1442868.

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Hoehn, Jack R. "Low-Temperature Deformation of Mixed Siliciclastic & Carbonate Fault Rocks of the Copper Creek, Hunter Valley, and McConnell Thrusts." Oberlin College Honors Theses / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1400002733.

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Horst, Alison Elizabeth. "Seismic Source Characterization of Faults in the Portland and Tualatin Basins and a Paleoseismic Study of the Gales Creek Fault, OR." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5267.

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Portland, OR lies within the tectonically active forearc of the Cascadia subduction zone. Several, potentially hazardous, northwest striking faults in and around the Portland Basin are classified as Quaternary active by the USGS, but little is known about their Holocene activity. Geologic and geodetic studies in the Pacific Northwest (PNW) document ongoing clockwise rotation of the region since at least 16 Ma. Models for crustal deformation in the PNW suggest northwest trending faults accommodate dextral shear inferred from increasing clockwise rotation rates west of Portland. I compiled structural information to improve the seismic source characterization of these faults, and using empirical scaling relationships for fault length and earthquake magnitude, I find that many of the faults in the region are capable of generating earthquakes of magnitude 6 to 7. The focus of this study is the Gales Creek fault (GCF) which is the longest northwest-trending fault in the study area with prominent geomorphic expression, located 35 km west of Portland. In addition to a seismogenic source characterization, I investigated the GCF through paleoseismic trenching to document the style and timing of surface deforming earthquakes. I interpret three surface rupturing earthquakes from stratigraphic and structural relationships in the trench. Radiocarbon samples from offset stratigraphy constrain these earthquakes to have occurred ~1,000, ~4,200 and ~8,800 calibrated years before present. The penultimate earthquake backtilted a buried soil into the hillslope creating accommodation space that was infilled by a colluvial deposit. The most recent earthquake faulted and formed a fissure within the penultimate colluvial deposit. My results suggest the GCF is active, and has experienced at least three surface-deforming earthquakes in the Holocene. New earthquake timing constraints presented here, combined with ongoing research on the central GCF will better constrain the lateral extent of prehistoric surface rupturing earthquakes, and can be used to refine magnitude estimates for the GCF.

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Mager, Stephanie M. Steltenpohl Mark G. "The Late- to Post-Caledonian extensional history of Northwest Hinnøy, North Norway." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/master's/MAGER_STEPHANIE_56.pdf.

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Hodge, Michael. "Development, deformation style, and seismic hazard of large normal faults." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/112226/.

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Young rifts such as the Malawi Rift System, located at the southern end of the East African Rift System, are a natural laboratory for how continents begin to break apart. Extension is typically accommodated by earthquakes within the upper crust. However, where extension occurs at a slow rate, the small number of historically recorded earthquakes likely provides an incomplete view of the potential magnitude range of events, limiting seismic hazard knowledge and the understanding of rift dynamics. Geological and geomorphological studies of faults scarps may help understand how faults develop, structurally evolve and accommodate displacement. Thus, in this thesis, using field and satellite observations of fault scarps, alongside numerical models, I develop a number of new methodologies in order to better understand young rift evolution. I show that the coseismic stress change between two active parallel faults influences whether the faults link, and the linkage style is determined by the distance between the faults. I also show that the orientation of a major border fault in a young rift can be influenced by local stresses and/or weakness at depth, forming faults oblique to what is expected by the regional stress field. Lastly, I identify segmentation on several Malawi Rift System faults from variations in scarp height and steps in the fault traces, and show that the morphology of each can be used to infer the number of prehistoric earthquake events. My work may suggest that large, normal faults in young rifts develop through a specific growth model, and that they can host earthquakes larger in magnitude than historically recorded. This research can help better understand rift evolution and earthquake hazard in the Malawi Rift System, as well as other regions where normal faults have the potential to cause large magnitude earthquakes, such as the Rukwa rift, Baikal rift and the Basin and Range Province.

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Farrell, Natalie Jane Charlotte. "Quantifying fault stability." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=229386.

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Guthrie, Kristin M. "Structural controls on extensional-basin development triassic Ischigualasto Formation, NW Argentina." Connect to this document online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1123266742.

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Thesis (M.S.)--Miami University, Dept. of Geology, 2005.
Title from first page of PDF document. Document formatted into pages; contains [1], iv, 38 p. : ill. Includes bibliographical references (p. 35-38).

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Hornsby, Kristofer Tyler. "Constraining the Holocene Extent of the Northwest Meers Fault, Oklahoma Using High-Resolution Topography and Paleoseismic Trenching." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3890.

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The Meers Fault (Oklahoma) is one of few seismogenic structures with Holocene surface expression in the stable continental region of North America. Only the ~37 km-long southeastern section of the ~55 km long Meers Fault is interpreted to be Holocene-active. The ~17 km-long northwestern section is considered to be Quaternary-active (pre-Holocene); however, its low-relief geomorphic expression and anthropogenic alteration have presented difficulties in evaluating the fault length and style of Holocene deformation. We reevaluate surface expression and earthquake timing of the northwestern portion of the Meers Fault to improve fault characterization, earthquake rupture models, and seismic hazard evaluations based on fault length. We use a combination of airborne lidar (0.5--2 m-resolution), historical aerial photos, and new balloon-based photogrammetric (Structure from Motion) topography (0.25--0.5 m-resolution) collected in this study to analyze and characterize the fault scarp and local fault zone geomorphology. In the northwest, complex surface deformation includes fault splays, a left step, subtle monoclinal warping, and a minor change in fault strike. The fault is evident in the landscape as linear escarpments, incised channels on the up-thrown side of the scarp, and closed depressions on the downthrown side. I use topographic profiles, measured perpendicular to the fault scarp to show that the northwest scarp is characterized by decimeter surface offsets. Where the fault traverses the Post Oak Conglomerate the fault zone width rarely exceeds 25 m, in the Hennessey Shale I document an increase in fault zone width with deformation occurring over 20 m to 115 m. I further examined the northwest section of the fault in a paleoseismic excavation where weathered Permian Hennessey Shale and a ~1--2 m-thick veneer of Holocene alluvial deposits have been folded and warped during three surface-folding earthquakes. In an adjacent stream exposure these units are also faulted near the ground surface. Paleoearthquake age modeling (Oxcal) constrained by accelerated mass spectrometry (AMS) dating of detrital charcoal and optically stimulated luminescence (OSL) dating of sandy alluvial beds indicates two earthquakes occurred since ~6152-5550 cal. years BP and one possibly older event along the erosional unconformity along the Hennessey Shale bedrock. This analysis lengthens the Holocene extent of the Meers Fault by ~6 km, to ~43 km, and extends the paleoseismic record of the Meers Fault to ~9598 cal. years BP. These data will improve fault-rupture and earthquake recurrence models used for seismic hazard analysis of the Meers Fault.

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Lock, Jane. "Interpreting how low-temperature thermochronometric data in fold-and-thrust belts : an example from the Western Foothills, Taiwan /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6698.

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Patthoff, D. Alex. "Structure and crustal balance of the Herald Arch and Hope Basin in the Chukchi Sea, Alaska." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5888.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains vii, 106 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 100-103).

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Soden, Aisling M. "The initiation and evolution of ignimbrite faults, Gran Canaria, Spain." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/191/.

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Understanding how faults initiate and fault architecture evolves is central to predicting bulk fault zone properties such as fault zone permeability and mechanical strength. The study of faults at the Earth’s surface and at near-surface levels is significant for the development of high level nuclear waste repositories, and CO2 sequestration facilities. Additionally, with growing concern over water resources, understanding the impact faults have on contaminant transport between the unsaturated and saturated zone has become increasingly important. The proposal of a high-level nuclear waste repository in the tuffs of Yucca Mountain, Nevada has stimulated interest into research on the characterisation of brittle deformation in non-welded to densely welded tuffs and the nature of fluid flow in these faults and fractures. The majority of research on the initiation and development of faults has focussed on shear faults in overall compressional stress regimes. Dilational structures have been examined in compressional settings e.g. overlapping faults generating extensional oversteps, or in normal faults cutting mechanical layered stratigraphy. Previous work has shown the affect mechanical stratigraphy has on fault dip angle; competent layers have steeply dipping segments and less competent layers have shallowly dipping segments. Displacement is accommodated by shear failure of the shallow segments and hybrid failure of the steeply dipping segments. As the fault walls of the shear failure segment slip past each other the walls of the hybrid failure segment are displaced horizontally as well as vertically thus forming dilation structures such as pull-aparts or extensional bends. Work on truly extensional faults has been at the kilometre scale of fissure swarms in rift systems where the focus is on fault geometry and direction of fault propagation. This study examines dilational faults with offsets of centimetres to 10’s of meters within moderately and densely welded ignimbrite units on the caldera island of Gran Canaria, Spain. Through the investigation of fault populations within different ignimbrite units I have examined how the fault architecture changes with accumulated displacement, identified the factors controlling fault core evolution and using these observations developed a new model for the initiation and growth of dilational faults in ignimbrites. The faults in this study do not have a linear correlation of increasing fault core thickness with displacement. Fault core width varies along fault dip and the largest offset faults have the narrowest fault cores. Furthermore, the damage zone joint frequency shows a limited increase with increasing displacement and faults and joints are sub-parallel. From these observations I have developed a new model for fault initiation and evolution in which the petrophysical properties of the host rock are the primary control on fault architecture. Faults initiate on existing sub-parallel joints and grow by the incorporation of material from joint surfaces and joint bound slabs. The growth of the fault depends on the joint spacing and the competency of the host rock. In densely welded ignimbrites, joint spacing is controlled by sub-layers within the ignimbrite unit which are formed by flattening and stretching of fiamme. In moderately welded ignimbrites, fiamme and lithic inclusions in the ash matrix act as sites of joint initiation; the greater the abundance of such flaws the higher the joint frequency. Whether fault growth is promoted or inhibited depends to some extent on the competency of the material. Faults cutting ash-rich friable units have narrow fault cores regardless of displacement. This suggests that the material is easily abraded in the fault core inhibiting fracturing of the host rock and incorporation of new material. Hence host rock fabric and composition have an important influence on fault architecture in these ignimbrite units. The other influence on fault evolution is the tensile stress regime in which faulting occurs. The faults in this study form by hybrid failure and so have both vertical and horizontal displacements. The dilation of existing joints causes slip on the joints and allows material to fall into the joint forming a fault core. This work identifies distinct differences between the mechanism of dilational fault initiation and resultant fault architecture compared to that of shear faults. The observations made in this study indicate that the host rock petrophysical properties, stress regime at time of faulting (tensile or compressive) and confining pressure are primary influences on fault architecture and not displacement; contradicting the widely accepted fault thickness-displacement scaling relationship. I suggest that the architecture of dilational faults can be predicted by examining the host rock properties and using the data from this study have developed a framework that illustrates how ignimbrite host rock properties may affect deformation structures. Such frameworks for individual lithologies may be more useful in predicting fault zone properties as opposed to global scaling relationships. The results of this study have implications for conceptual models of fluid flow based on fault architectures predicted using the thickness-displacement relationship.

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Wild, Christopher. "The propagation of strike-slip faults using 3D seismic data." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/87446/.

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The application of 3D seismic data to the study of fault evolution has greatly increased our understanding of how normal and thrust faults propagate. Specifically, by combining displacement distribution plots and a thorough analysis of the fault geometry, we can determine: linkage history, restrictions to fault growth, and blind versus emergent propagation. However, these methods have never been applied to strike-slip faults in seismic data due to the difficulty in imaging kinematic indicators or piercing points that quantify displacement. This thesis presents a novel technique that allows for the rapid identification of kinematic indicators in two 3D seismic datasets from the Levant Basin, Eastern Mediterranean, which enables the displacement distribution of strike-slip faults to be analysed beyond what has been accomplished by traditional field-based studies. The high quality of the data also enables the detailed investigation into the 3D geometry of strike-slip faults to be used in conjunction with the displacement data to better understand the upward vertical propagation history. Results indicate that high displacement faults show distinctly different geometries from low displacement faults, and that strain rate and propagation mode may be integral in controlling geometry type. Furthermore, the geometry of the naturally occurring examples presented here, shows distinct differences from analogue studies, and suggests future work should be applied to understanding what controls these discrepancies. The displacement distribution also allowed insight into fault network relationships at the regional scale, in addition to individual faults. In particular, the 3D geometry of conjugate intersections, branching intersections, and tip structures was explored. The results yielded very complex and confounding structural relationships, which suggest that deformation is rarely as simple as 2D interpretations show, and thus may have significant consequences to precious resource extraction.

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Hull, Jonathan N. F. "Sequence stratigraphic evolution of the Albian to recent section of the Dampier Sub-basin, North West Shelf, Australia." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phh9128.pdf.

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Four folded maps in pocket on back cover. Copy of author's previously published work inserted. Includes bibliographical references (9 leaves). An integrated biostratigraphic, wireline, seismic, lithological and 3D-Chronostrat sequence stratigraphic study has been conducted to investigate the evolution of the Albian to recent section of the Dampier Sub-basin on Australia's North West Shelf,.

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Mohapatra, Gopal Krishna 1968. "Faulting and basin geometry beneath the Great Salt Lake: implications for basin evolution and cenozoic extension." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/565551.

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Fang, Zijun. "Earthquake nucleation on geometrically complex faults." Diss., [Riverside, Calif.] : University of California, Riverside, 2009. http://proquest.umi.com/pqdweb?index=0&did=1957308721&SrchMode=2&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1269013342&clientId=48051.

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Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 20, 2010). Includes bibliographical references. Also issued in print.

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Delwiche, Benjamin M. "Oligocene paleotopography and structural evolution of the Pah Rah Range, western Nevada implications for constraining slip on the right-lateral Warm Springs Valley fault in the northern Walker Lane /." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446438.

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Clark, Cameron Wilhite. "Investigation into the Niobrara Formation and Missing Section Associated with Pre-lithification Faults, Wattenberg Field (CO)." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10817209.

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The Denver-Julesburg Basin (DJ Basin) has been a productive oil and gas field since 1970 where operators began targeting the J sandstone (Sonnenberg 2013). Within the DJ Basin, the Wattenberg field has been the ?hot spot? for the past several years due to its high gas to oil ratio. The Niobrara Formation has added new value to this area as the use of horizontal drilling and hydraulic fracturing has become common practice for operators in the Wattenberg since 2009 (Sonnenberg 2013). This formation is a ?tight? rock that has very little connectivity making the hydraulic fracturing technique a necessity for economical wells. There are a large number of faults seen in the Wattenberg field that can have just a few feet of displacement to very large faults with 100+ feet of displacement. These faults are likely part of a polygonal fault system that has been linked to dewatering events that occurred prelithification in the Wattenberg Field (Underwood 2013). Along some of these major faults we see sections of Niobrara Formation that are missing, and these fault planes provide a pathway for the expulsion of this sediment. Understanding the pre-lithification faulting and missing section in the Niobrara Formation could result in added economic value as this could lead to finding optimal well placement for maximizing oil recovery. This study was driven by the hypothesis that the missing section of Niobrara Formation could be linked to the Pierre Shale?s Tepee Buttes. To determine the origin of the Tepee Buttes seismic data, well logs, thin sections, and XRF data was used to further investigate the Tepee Buttes, Niobrara Formation Chalks and Marls, Fort Hays Limestone, and Pierre Shale.

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Millard, Mark Alan Cronin Vincent S. "Linking onshore and offshore data to find seismogenic faults along the Eastern Malibu coastline." Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5109.

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Whitmarsh, Richard Sawyer. "Structural framework of the Fries fault zone south of Riner, Virginia." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-09122009-040538/.

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Hill, Matthew P. "Evolution of quartz and calcite microstructures exhumed from deep brittle-ductile shear zones in the Southern Alps of New Zealand : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Geology /." ResearchArchive@Victoria e-Thesis, 2005. http://hdl.handle.net/10063/33.

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Villa, Danielle E. "Late Paleozoic deformation at Edna Mountain, Humboldt County, Nevada." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1447592.

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Thompson, Stephen C. "Active tectonics in the central Tien Shan, Kyrgyz Republic /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/6744.

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Brush, Jennifer. "Faults and fractures in the Niobrara Formation of Wattenberg Field, Colorado." Thesis, Colorado School of Mines, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10128859.

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Faults are an important element of reservoir characterization because they have the potential to compartmentalize a reservoir and create associated fractures that can profoundly influence fluid flow in the reservoir. This investigation describes details of the fault regime in a portion of the Wattenberg Field, Colorado. For the purposes of this study, seismic-scale faults are interpreted as horizons with displacements. Seismic-scale fractures are interpreted as linear amplitude discontinuities. Borehole image log scale faults show displacement. Borehole image log scale fractures do not show displacement. Both borehole image log scale faults and fractures are interpreted as seismic-scale fractures.

Faults were discovered by interpreting inflection points in cumulative dip plots and azimuth walkout plots derived from a borehole image log in a vertical well. On the image log fractures are consistently found in both the Niobrara chalk and marl benches. The individual benches are not resolvable at the scale of the seismic data, but evidence that faults are present in both the chalks and marls lends credence to the potential that seismic data may be able to predict fracture zones either directly or indirectly.

The hypothesis is tested on a 50 square mile 3D seismic survey. Generally, faults present in the Niobrara Formation in the survey are planar, normal faults that range up to two miles in length. Over 150 faults were picked. Rose diagrams illustrate a predominant strike direction of N 20 E. A predictive fracture volume was generated utilizing CGG’s proprietary software: InsightEarth™. The algorithm generates this volume statistically based on fault geometry. Each seismic-scale fault indicates a high potential for fracture swarms in the nearby vicinity. Fracture prediction can assist future exploration and development in the Niobrara resource play.

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Toy, Virginia Gail, and n/a. "Rheology of the Alpine Fault Mylonite Zone : deformation processes at and below the base of the seismogenic zone in a major plate boundary structure." University of Otago. Department of Geology, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080305.110949.

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The Alpine Fault is the major structure of the Pacific-Australian plate boundary through New Zealand�s South Island. During dextral reverse fault slip, a <5 million year old, ~1 km thick mylonite zone has been exhumed in the hanging-wall, providing unique exposure of material deformed to very high strains at deep crustal levels under boundary conditions constrained by present-day plate motions. The purpose of this study was to investigate the fault zone rheology and mechanisms of strain localisation, to obtain further information about how the structural development of this shear zone relates to the kinematic and thermal boundary constraints, and to investigate the mechanisms by which the viscously deforming mylonite zone is linked to the brittle structure, that fails episodically causing large earthquakes. This study has focussed on the central section of the fault from Harihari to Fox Glacier. In this area, mylonites derived from a quartzofeldspathic Alpine Schist protolith are most common, but slivers of Western Province-derived footwall material, which can be differentiated using mineralogy and bulk rock geochemistry, were also incorporated into the fault zone. These footwall-derived mylonites are increasingly common towards the north. At amphibolite-facies conditions mylonitic deformation was localised to the mylonite and ultramylonite subzones of the schist-derived mylonites. Most deformation was accommodated by dislocation creep of quartz, which developed strong Y-maximum crystallographic preferred orientation (CPO) patterns by prism (a) dominant slip. Formation of this highly-oriented fabric would have led to significant geometric softening and enhanced strain localisation. During this high strain deformation, pre-existing Alpine Schist fabrics in polyphase rocks were reconstituted to relatively well-mixed, finer-grained aggregates. As a result of this fabric homogenisation, strong syn-mylonitic object lineations were not formed. Strain models show that weak lineations trending towards ~090� and kinematic directions indicated by asymmetric fabrics and CPO pattern symmetry could have formed during pure shear stretches up-dip of the fault of ~3.5, coupled with simple shear strains [greater than or equal to]30. The preferred estimate of simple:pure shear strain gives a kinematc vorticity number, W[k] [greater than or equal to]̲ 0.9997. Rapid exhumation due to fault slip resulted in advection of crustal isotherms. New thermobarometric and fluid inclusion analyses from fault zone materials allow the thermal gradient along an uplift path in the fault rocks to be more precisely defined than previously. Fluid inclusion data indicate temperatures of 325+̲15�C were experienced at depths of ~45 km, so that a high thermal gradient of ~75�C km⁻� is indicated in the near-surface. This gradient must fall off to [ less than approximately]l0�C km⁻� below the brittle-viscous transition since feldspar thermobarometry, Ti-inbiotite thermometry and the absence of prism(c)-slip quartz CPO fabrics indicate deformation temperatures did not exceed ~ 650�C at [greater than or equal to] 7.0-8.5�1.5 kbar, ie. 26-33 km depth. During exhumation, the strongly oriented quartzite fabrics were not favourably oriented for activation of the lower temperature basal(a) slip system, which should have dominated at depths [less than approximately]20 km. Quartz continued to deform by crystal-plastic mechanisms to shallow levels. However, pure dislocation creep of quartz was replaced by a frictional-viscous deformation mechanism of sliding on weak mica basal planes coupled with dislocation creep of quartz. Such frictional-viscous flow is particularly favoured during high-strain rate events as might be expected during rupture of the overlying brittle fault zone. Maximum flow stresses supported by this mechanism are ~65 Mpa, similar to those indicated by recrystallised grain size paleopiezometry of quartz (D>25[mu]m, indicating [Delta][sigma][max] ~55 MPa for most mylonites). It is likely that the preferentially oriented prism (a) slip system was activated during these events, so the Y-maximum CPO fabrics were preserved. Simple numerical models show that activation of this slip system is favoured over the basal (a) system, which has a lower critical resolved shear stress (CRSS) at low temperatures, for aggregates with strong Y-maximum orientations. Absence of pervasive crystal-plastic deformation of micas and feldspars during activation of this mechanism also resulted in preservation of mineral chemistries from the highest grades of mylonitic deformation (ie. amphibolite-facies). Retrograde, epidote-amphibolite to greenschist-facies mineral assemblages were pervasively developed in ultramylonites and cataclasites immediately adjacent to the fault core and in footwall-derived mylonites, perhaps during episodic transfer of this material into and subsequently out of the cooler footwall block. In the more distal protomylonites, retrograde assemblages were locally developed along shear bands that also accommodated most of the mylonitic deformation in these rocks. Ti-in-biotite thermometry suggests biotite in these shear bands equilibrated down to ~500+̲50�C, suggesting crystal-plastic deformation of this mineral continued to these temperatures. Crossed-girdle quartz CPO fabrics were formed in these protomylonites by basal (a) dominant slip, indicating a strongly oriented fabric had not previously formed at depth due to the relatively small strains, and that dislocation creep of quartz continued at depths [less than or equal to]20 km. Lineation orientations, CPO fabric symmetry and shear-band fabrics in these protomylonites are consistent with a smaller simple:pure shear strain ratio than that observed closer to the fault core (W[k] [greater than approximately] 0.98), but require a similar total pure shear component. Furthermore, they indicate an increase in the simple shear component with time, consistent with incorporation of new hanging-wall material into the fault zone. Pre-existing lineations were only slowly rotated into coincidence with the mylonitic simple shear direction in the shear bands since they lay close to the simple shear plane, and inherited orientations were not destroyed until large finite strains (<100) were achieved. As the fault rocks were exhumed through the brittle-viscous transition, they experienced localised brittle shear failures. These small-scale seismic events formed friction melts (ie. pseudotachylytes). The volume of pseudotachylyte produced is related to host rock mineralogy (more melt in host rocks containing hydrated minerals), and fabric (more melt in isotropic host rocks). Frictional melting also occurred within cataclastic hosts, indicating the cataclasites around the principal slip surface of the Alpine Fault were produced by multiple episodes of discrete shear rather than distributed cataclastic flow. Pseudotachylytes were also formed in the presence of fluids, suggesting relatively high fault gouge permeabilities were transiently attained, probably during large earthquakes. Frictional melting contributed to formation of phyllosilicate-rich fault gouges, weakening the brittle structure and promoting slip localisation. The location of faulting and pseudotachylyte formation, and the strength of the fault in the brittle regime were strongly influenced by cyclic hydrothermal cementation processes. A thermomechanical model of the central Alpine Fault zone has been defined using the results of this study. The mylonites represent a localised zone of high simple shear strain, embedded in a crustal block that underwent bulk pure shear. The boundaries of the simple shear zone moved into the surrounding material with time. This means that the exhumed sequence does not represent a simple 'time slice' illustrating progressive fault rock development during increasing simple shear strains. The deformation history of the mylonites at deep crustal P-T conditions had a profound influence on subsequent deformation mechanisms and fabric development during exhumation.

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Rigby, Michael Gomez Francisco Gustavo. "Recent faulting and active shortening of the Middle Atlas Mountains, Morocco, within the diffuse African-Eurasian plate boundary." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5796.

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Thesis (M.S.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on July 8, 2009) Includes bibliographical references.

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Leung, Alfreda. "Identification of fault zones using gravity survey and subsurface exploration : a case study /." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B42577664.

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Treerotchananon, Anuwat 1979. "Extension between Major Faults, Central Oregon Basin and Range." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10082.

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xi, 60 p. : ill. (some col.), maps (some col.). A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
I present an alternative approach to determine the magnitude and direction of extension in the Basin and Range Province at the north end of Summer Lake basin using GIS techniques. Offset across 161 faults and tilting of 56 fault blocks were estimated to calculate extension as a function of azimuth in this area. The orientation of a representative set of slickenlines was collected in the field to assign average values for the GIS analysis. Azimuthal variation of extension is consistent with a strain ellipse indicating plane strain with extension of 1.5 to 5.5 percent along the maximum extension direction of N75E and no extension along the minimum N15W axis. Blocks tilt on average 60° from the maximum extension direction, suggesting the underlying detachment dips -N15E. This technique allows strain associated with the numerous small faults to be added to the sparse large faults for a complete regional analysis.
Committee in Charge: Dr. Ray Weldon, Chair; Dr. David Schmidt; Dr. Marli Miller

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Ward, Emily M. Geraghty. "Development of the Rocky Mountain foreland basin combined structural, mineralogical, and geochemical analysis of basin evolution, Rocky Mountain thrust front, northwest Montana /." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-09262007-094800/.

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Dissertations / Theses on the topic 'Faults (geology)'

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